Is he warning me or hinting something?

Me and this guy I used to know have been texting for a while, lately he has been telling me that he is a bad boy but tells me he is trying to change his ways because I won't be able to handle his "bad" boy side. I asked what does he mean, and he said that he is controlling his bad side.

Now we have not dated nor seen each other for a while, he admitted he had a crush on me in high school and now tells me he likes how I am. He texts me everyday, if I don't text back he will text sad faces and the next day he will write a paragraph of his feelings (which confuse me).